The present invention is directed to a system for detecting the identification of a card that is installed in an input/output interface, and more particularly to a system for identifying the type of card that may be installed in an input/output interface between two electronic components, such as a peripheral device and a peripheral control device, for example.
As the functional capabilities of electronic products continue to expand, new products continue to be developed which must be compatible across manufacturers"" product lines. This is particularly evident in the areas of personal computers that are used in the home and in large and small business environments, which may or may not be connected in a network or the Internet. Such personal computers are usually operationally connected to peripheral devices such as printers of various kinds, plotters, scanners, fax machines, copiers and the like, including multi-function peripherals which can perform the more than one task of those mentioned above.
One of the relatively recent advancements in the design of peripheral devices is the expansion of their operational capabilities through the use of cartridges or cards that can be plugged into a shared input/output interface of the peripheral device that is intended to operate in conjunction with a control device. Such cards can be so-called peripheral dependent cards which can implement basic functionality, or they can be smart cards which typically includes operational protocol that can increase the functional capability of the peripheral in conjunction with a control device, such as a print server, for example.
Because different types of cards may be plugged into the interface, it is necessary to know the identity of the type of card that is plugged into the interface of a peripheral device so that the functionality and configuration are supported in the system. Since the peripheral device is the device that is generally considered to be the master device in a system that wishes to perform the peripheral device function, i.e., a printer, for example, must have the necessary input control commands to operate properly. It is the peripheral device that must support the cards that may be plugged into the peripheral interface.
If the peripheral device does not support a particular card, then damage to the card and/or the peripheral device can easily occur if output signals are not applied to output lines, and input signals are not applied to input lines. It is therefore extremely important that the system be appropriately configured so that damage resulting from device interconnection incompatibility does not occur.
The present invention embodies a system and a method for detecting the identification of the type of card or cartridge that may be plugged into an electrical interface that interconnects two electronic devices, such as a peripheral device and a peripheral control device. Because the cards may have different functionality and utilize different configurations, it is important that the peripheral device support the functionality of the card that is plugged into the interface. Upon start-up, the peripheral device generates a signal which causes the card to generate a digital identification that is received by the peripheral device. If the identification indicates that it is a type of card that the peripheral device supports, then the peripheral device operates in the manner specified for that type of card. The preferred embodiment of the card is an implementation that requires only a single pin to reset a chip and generate the digital identification, and therefore requires only minimal overhead in the design and operation of the input/output interface.